1. Field of the Invention
The present invention relates to an endoscope and an endoscope system with which can be replaced a therapeutic instrument by using a guide wire in endoscopy or endoscopic surgery of pancreaticobiliary ducts in particular.
2. Description of the Related Art
In recent years, use of an endoscopic treatment for treatment of a disorder in an alimentary canal system and a pancreaticobiliary duct system is increasing. As the current treatment for the pancreaticobiliary duct system using an endoscope, there is a diagnostic treatment for endoscopically imaging a bile duct or a pancreatic duct as well as therapeutic treatment for collecting a bile stone existing in a choledoch duct by a balloon or a gripping therapeutic instrument.
Further, in the endoscopic treatment for a pancreatic duct, a bile duct or a hepatic duct, an end of an insertion portion of the endoscope is inserted to the vicinity of the duodenal papilla, and a therapeutic instrument such as a catheter is then selectively inserted into the pancreatic duct or the bile duct with a guide wire as a guide in radioscopy.
Furthermore, when performing endoscopic treatment for a pancreatic duct, a bile duct or a hepatic duct by using the endoscope, the end of the insertion portion of the endoscope is usually inserted to the vicinity of the duodenal papilla, and a therapeutic instrument such as a catheter is then generally selectively inserted into the pancreatic duct or the bile duct with the guide wire as a guide, in radioscopy.
Specifically, the following operation is carried out. At first, after an end portion 903 of an insertion portion 902 of an endoscope 901 shown in FIGS. 114A and 114B is inserted to the vicinity of duodenal papilla in advance, a catheter 904 is inserted into a therapeutic instrument insertion channel of the endoscope 901, and an end portion 904a of the catheter 904 is endoscopically inserted into the pancreatic duct or the bile duct. Then, a guide wire 905 is inserted from a mouth ring 904b of the inserted catheter 904 on the base end side.
Thereafter, in radioscopy, it is confirmed that the guide wire 905 is correctly inserted into the pancreatic duct or the bile duct, and the operation for pulling out the catheter 904 from the therapeutic instrument insertion channel of the endoscope 901 is carried out while gripping the base end side of the guide wire 905 by hand as shown in FIG. 114A. During this operation, as shown in FIG. 114B, when the end portion 904a of the catheter 904 protrudes from a channel opening portion 907 on an operation portion 906 side of the endoscope 901, the guide wire 905 in the vicinity of the channel opening portion 907 of the endoscope 901 is gripped, and the catheter 904 is completely pulled out of the endoscope 901.
Subsequently, the base end side of the guide wire 905 is inserted into an insertion hole of another therapeutic instrument, and this therapeutic instrument is inserted into the therapeutic instrument insertion channel of the endoscope 901 so as to be guided by the guide wire 905. Thereafter, the above-described operation is repeated in accordance with a number of times of replacement of the therapeutic instrument.
The therapeutic instrument used for such treatment is generally set to have a length which is not less than 190 cm by taking a length of the endoscope 901 into consideration.
Furthermore, since a length which exceeds a combination of a length of the endoscope 901 and that of the therapeutic instrument is required for the guide wire 905, at least approximately 400 cm is necessary.
Moreover, for example, U.S. Pat. No. 5,921,971 discloses a bile duct catheter which can be rapidly replaced by providing an opening portion in the longitudinal direction between an end portion of a guide wire lumen and a base end portion in a catheter shaft.
Meanwhile, in case of observing/treating the pancreaticobiliary duct system by using the endoscope 901, when a therapeutic instrument such as the catheter 904 is inserted into the therapeutic instrument insertion channel of the endoscope 901 and used, the guide wire 905 is inserted into the therapeutic instrument. Therefore, when the therapeutic instrument is moved with respect to the endoscope 901, the guide wire 905 also simultaneously moves. Thus, for example, when replacing the therapeutic instrument with the guide wire 905 as a guide in the state where the end of the guide wire 905 is inserted into the papilla, the guide wire 905 must be constantly gripped on the operation portion 906 side of the endoscope 901 in order to maintain the end of the guide wire 905 being inserted into the papilla.
In addition, during use of the conventional endoscope 901, it is necessary to simultaneously carry out the two operations, i.e., pulling out the therapeutic instrument with respect to the therapeutic instrument insertion channel of the endoscope 901 while inserting the guide wire 905 by the same amount in the operation for replacing the therapeutic instrument, or similarly inserting the therapeutic instrument into the therapeutic instrument insertion channel while pulling out the guide wire 905 by the same movement amount. Therefore, that operation is complicated and troublesome.
Additionally, since the guide wire 905 has a length of approximately 400 cm, it is difficult to handle the guide wire 905 in such a manner that the guide wire 905 does not come into contact with an unclean area such as the floor in a small endoscope room.
Further, since the therapeutic instrument can not be replaced unless the entire length of the guide wire 905 is moved, the time required for replacement of the therapeutic instrument itself may possibly be prolonged. Therefore, there is a drawback that the operation for replacing the therapeutic instrument takes longer.
Furthermore, it is difficult for one operator to carry out the operation for replacing the therapeutic instrument, and at least two assistants are required in an operating room. Therefore, there occurs a problem that the personnel cost increases and the pecuniary burden on a hospital or a patient thereby increases.
Moreover, as in U.S. Pat. No. 5,921,971, in the case of the catheter having the opening portion in the longitudinal direction being provided between the end portion and the base end portion of the guide wire lumen in the catheter shaft, the operation for providing the opening portion in the longitudinal direction to the conventional contrasting catheter. Thus, there is a drawback that the manufacturing cost is higher than that of the conventional contrasting catheter.
In addition, an outside diameter of the shaft must be increased in order to compensate for a reduction in rigidity of the catheter shaft caused due to provision of a slit, or a material of the shaft must be hardened. Therefore, an increase in diameter of the shaft may possibly lead to deterioration of the working property of an operator since the insertion ability in the channel of the endoscope is degraded.
Additionally, since the treatment for the pancreaticobiliary duct system requires specialist techniques, preference of the operator with respect to therapeutic instruments is divided in particular. Further, changing the therapeutic instruments depending on conditions of a patient is frequently carried out. However, usable therapeutic instruments are restricted in this prior art by itself, and the selection range of the operator is disadvantageously lost.
In view of the above-described problems, it is an object of the present invention to provide an endoscope apparatus by which a therapeutic instrument can be replaced in a shorter time and the replacement operation can be performed by one operator without impairing the conventional operation method of a therapeutic instrument or the operation sense.